f2fs: change reclaim rate in percentage

It is more reasonable to determine the reclaiming rate of prefree segments
according to the volume size, which is set to 5% by default.
For example, if the volume is 128GB, the prefree segments are reclaimed
when the number reaches to 6.4GB.

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/Documentation/filesystems/f2fs.txt b/Documentation/filesystems/f2fs.txt
index f415b9fc4cc8..2f6d0218dd22 100644
--- a/Documentation/filesystems/f2fs.txt
+++ b/Documentation/filesystems/f2fs.txt
@@ -169,9 +169,11 @@ Files in /sys/fs/f2fs/<devname>
 
  reclaim_segments             This parameter controls the number of prefree
                               segments to be reclaimed. If the number of prefree
-                              segments is larger than this number, f2fs tries to
-                              conduct checkpoint to reclaim the prefree segments
-                              to free segments. By default, 100 segments, 200MB.
+                              segments is larger than the number of segments
+                              in the proportion to the percentage over total
+                              volume size, f2fs tries to conduct checkpoint to
+                              reclaim the prefree segments to free segments.
+                              By default, 5% over total # of segments.
 
  max_small_discards           This parameter controls the number of discard
                               commands that consist small blocks less than 2MB.